Flame cutting apparatus for bars

ABSTRACT

The flame cutting apparatus comprises a movable construction unit containing supporting rollers for the continuous bar to be cut off, a gas cutting torch, and clamping jaws for the bar. Stationary first and second discharging rollers are disposed in alignment with the path of movement of the bar. The leading supporting roller in the construction unit is situated ahead of the torch and at its end position it cooperates with the discharging rollers in supporting the cut-off bar section.

nite States Patent [191 Pieutier et all.

[ FLAME CUTTING APPARATUS FOR BARS [75 lnventors: Alfred Pfeufl'er,Neu-Isenburg;

Helmut Weber, Steinbach/TS; Hans Joachim Sach, Harheim, all of Germany[73 l Assignee: Messer Grieshum GmbH, Hanauer Landsbrasse, Germany 221Filed: Nov. 29, 1972 21 App]. No.: 310,600

Related U.S. Application Data [63] Continuation of Ser. No.7l,847,"Sept. 14, 1970,

abandoned.

[30] Foreign Application Priority Data Sept. 18, 1969 Germany P 19 47282.3

[52] U.S. Cl..... 266/23 K, 164/263, 266/23 M [51] Int. Cl B23k 7/10,B22d 11/12 [58] Field of Search 266/23 K, 23 M;

[56] References Cited UNITED STATES PATENTS 3,291,470 12/1966 Lotz266/23 M 3,382,112 5/1968 Oxley et al 266/23 K X Primary Examiner-RobertD. Baldwin Attorney-Ernest F. Marmorek [57] ABSTRACT The flame cuttingapparatus comprises a movable construction unit containing supportingrollers for the continuous bar to be cut off, a gas cutting torch, andclamping jaws for the bar. Stationary first and second dischargingrollers are disposed in alignment with the path of movement of the bar.The leading supporting roller in the construction unit is situated aheadof the torch and at its end position it cooperates with the dischargingrollers in supporting the cut-off bar section.

3 Claims, 2 Drawing Figures Patented Oct. 23, 1973 3,767,778

Fig. 1

.i 7.77/ AW 20 Y .1" H! W I r 5 I E3+ l MT E I i 21 L Fig. 2

IN VEN TORS FLAME CUTTING APPARATUS FOR BARS This is a continuation ofapplication Ser. No. 71,847, filed Sept. 14, 1970, now abandoned.

BACKGROUND OF THE INVENTION The invention relates generally to a flamecutting apparatus for a continuous bar. More particularly, this invention relates to a supporting arrangement for the cutoff bar sections.

From prior art a flame cutting apparatus for bars is known in which atleast two support rollers for'the bar, the cutting torch, and theclamping means for achieving synchronous running of the bar and torchare grouped together in a constructional unit which is movable on arunning track in the region of the cutting station.

A constructional unit of this kind is known from German Pat. No.1,233,109. It has now been found that when short workpieces are cut offthere is a danger that these will tip off the discharging roller set anddrop into 1 the cutting pit. This may cause damage to the cuttingequipment and'to the roller bed, while not inconsiderable effort isinvolved in retrieving this cut off bar section from the cutting pit.

SUMMARY OF THE INVENTION An object of this invention, thus, is toprovide a new and improved arrangement of the constructional unit in theflame cutting apparatus for bars which would avoid the disadvantages ofprior art.

More specifically, it is an object of the invention to provide aconstructional unit that can also be used for transporting short lengthsof the cut off bar sections.

Another object of this invention is to provide a constructional unit inthe flame cutting apparatus, which can be employed as a supportingdevice for guiding the leading end portion of the continuous bar throughthe cutting station at the beginning of the cutting operation.

Still another object of this invention is to provide a constructionalunit which can be used as an additional roller bed in the region of thecutting station.

According to the invention it is proposed that at least one supportingroller should be disposed ahead of the cutting torch in reference to thedirection of movement of the bar, and the distance a b, where a is thedis tance from the end of the cut-off bar section to the axial center ofthe front support roller in its end position, and b is the distance fromthe axial center of the frnt support roller in the end position to theaxial center of the first roller of the discharging roller set, beingsmaller than half the length of the shortest bar section to be cut off.

It is thereby insured that no further components are necessary forsupporting the starting or dummy bar section over the cutting pitbetween two roller sets. The steps taken in accordance with theinvention enable that the above mentioned objects are attained in themost effective manner. The solution offered by the invention enablesthat prior art supporting rollers, chains, or additional, lowerablerollers in the region of the cutting station can be dispensed with, andthe entire installation thus becomes simplified.

In a further development of the invention it is proposed that theconstructional unit be provided with a device for the adjustment of thezero position (the starting position for commencing the cut), which willenable the cut to be started from various positions along the cuttingstation, with the object of insuring that the supporting roller disposedahead of the torch will be situated at the end of the running track inthe immediate proximity of the discharging roller set after thecompletion of the cut or, in any case, at the moment when the length ofthe cut-off bar section passes the supporting roller. Hitherto thebeginning of the cutting station was selected as a starting position forall cuts, while the end of the cut occurred at various positions in theregion of the cutting station depending on the casting speed, thecutting speed, and the crosssection to be cut.

The apparatus according to the invention, in conjunction with theadditional roller, thus enables that the end of the cut is situatedwithin the cutting station in such a manner that the length of thecut-off bar section is prevented from projecting from the dischargingroller set into the cutting station.

The length of the cutting station is designed with a safety margin,since due to different qualities of the bar material, an interruption ofcutting must in some cases be expected, and it should be possible torepeat the cut in this case; in cases where the cutting proceedsnormally and is not interrupted, the automatic clamping device remainsconnected to the bar even after the completion of the cutting until thecondition is fulfilled that the center of gravity of the length of thecut-off bar section lies on the discharge roller set, subsequently, theautomatic flame cutting device returns to its starting position.

In the case of very short bar sections when it is to be feared that theunsupported front end portion of the bar will sag as the bar movesfroward and before the new cutting commences, a simple control enablesthe automatic flame cutting device to be retained at the end of therunning track, on completion of the preceding cut, until the followingbar rests on the discharging roller set.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWING For a betterunderstanding of the invention, referencesis had to the followingdescription of an exemplary embodiment thereof taken in connection withthe accompanying drawing, in which FIG. 1 is an elevational view of theflame cutting apparatus for bars in accordance with the invention, and

FIG. 2 is a plan view of the principal parts of the apparatus of FIG. 1.

DETAILED DESCRIPTION Between a transport roller set 1, which follows thetrain of driving and leveling rolls (not illustrated), and the dischargeroller set 2 there is disposed a cutting pit 3 of a bar flame cuttingassembly. Above this cutting pit 3 there is disposed a track 4 on whicha constructional unit consisting basically of supporting rollers 5, 6, acutting torch 7, and clamping means 8 is movably supported on wheels 22of a carriage. The constructional unit 10 is moved by means of a chaindrive 9. The ends of the chain 9 are fastened at points 10 and 11 of thetrack and a loop of the chain runs over the guide roller 12, the driveroller 13 and a guide roller 14 disposed on the same shaft as that ofthe roller 5. As can be seen from the drawing, the front support roller6, which is mounted in the same way as the supporting roller 5 on anaxle shared with the wheels for the carriage, is situated ahead of thetorch 7.

According to another feature of this invention, the front supportingroller 6 at the end position of the travel of the construction unit isrelated to the discharging roller set 2 in such a manner that the sum ofthe distance a from the cut-off end of the bar section 21 to the axialcenter of the front supporting roller 6, and of the distance b from theaxail center of the front supporting roller 6 to the axial center of thefirst roller 19 of the discharging roller bed 2, is smaller than halfthe length l of the shortest predetermined bar section to be cut off.

In addition, limit switches a, 15b and 16 cooperating with adjustableearns 17, 18 are fastened on the movable constructional unit.

The mode of the bar dividing operation of the apparatus is as follows:

In the starting zero position of the constructional unit, asillustrated, clamp jaws 8 firmly connect this unit to the moving bar.After clamping has been effected the dividing cut starts and theconstructional unit moves synchronously with the bar in the direction ofthe discharge roller set 2. Shortly before reaching the cam 18 thedividing operation is completed and the constructional unit isdisconnected from the bar through the release of the damp jaws 8. Inthis position the supporting roller 6 and the torch 7 are situated asshown in dot-and-dash lines in FIG. 1. Together with the supportingrollers 19, 20 of the discharge roller set 2 the supporting roller 6serves as a support for the cut off length of the bar section 21. Thesmall cut-off bar sections are thus prevented from tipping off thedischarge roller into the cutting pit 3 after cutting has beencompleted. As soom as the cut-off bar section 21 has left the supportingroller 6, the constructional unit returns at a high speed to its zeroposition; the high speed back travel is first switched off by the limitswitch 5a actuated by the cam 17 and, subsequently, all movement isstopped by the action of the limit switch 15b and the cam 17. Theapparatus is then ready to make another cut.

In the cutting of longer bar sections, when the major portion of thesection is already situated on the roller set 2, it is not necessary tohold the constructional unit in its end position until the end of thecut-off bar section 21 is out of contact with the supporting roller 6.The limit switch can adjust the starting position of the movableconstruction unit so that the resulting bar advance Szy taking placeduring the cutting operation is shorter than the predetermined length lof the cut-off bar section 21.

It is possible for the constructional unit to return to the zeroposition immediately after the completion of the cutting action.

The support of the dummy bar, that is of the leading bar position beforethe first cut is started, is effected in the following manner: Theconstructional unit is in its zero position. The oncoming dummy bar orthe leading position of the bar passes from the roller set 1 over thesupporting roller 5 on to the supporting roller 6. The bar is thenguided through the cutting stationby clamping the constructional unit tothe dummy bar so long,

until the bar is transferred to the discharge roller set 2. Theconstructional unit thereupon returns to its zero position and becomesready to start the subsequent cutting. It is also conceivable for theconstructional unit to be moved in the direction of the discharge rollerset 2 by means of its own drive, synchronously with the dummy bar,without being clamped to it. In the case of shorter cutting stations itis also sufficient to place the constructional unit in the middle of therunning track.

The apparatus according to the invention may also be used with advantagefor cutting off the end portion of the bar, since owing to thearrangement of the supporting roller 6 ahead of the cutting torch 7 onlythe part between the torch and the clamp jaws 8 is left over and thiscan simply be discarded by opening the automatic clamping device in adetermined position, being for example thrown on to a scrapchutedisposed under the cutting station.

We wish it to be understood that we do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

Having thus described the invention, what we claim as new and desire tobe secured by Letters Patent, is as follows:

1. A flame cutting apparatus, for a continuous bar selectively movablein one direction,

comprising in combination,

stationary transport rollers,

stationary discharging rollers,

a movable cutting unit including wheels supporting the unit for movementin said one direction and opposite therk-gto between a bar receivingposition adjacent said transport rollers spaced apart from saiddischarging rollers, and, respectively, after moving in said onedirection, a discharging position adjacent said discharging rollers,said cutting unit further including two supporting rollers for the bar,said supporting rollers being mounted concentrically with said wheels;releasable clamping means for the bar, control means operable forenergizing said clamping means to clamp the bar thereby to insure thetemporary synchronous movement of the bar with said movable unit in saidone direction,

said control means including means operable for releasing said clampingmeans in said discharging position,

at least one flame cutting torch positioned in advance of said clampingmeans in said one direction,

one of said supporting rollers arranged in advance of said torch in saidone direction at such a distance from said torch as to support atrailing end portion of a predetermined bar section to be cut-off whensaid unit is near said discharge position with the other end of thecut-off bar section supported by at least one of said dischargingrollers, the major portion of said section in said discharge positionbeing supported by said discharging rollers;

a chain drive including a chain extending between said receiving anddischarging positions, and a drive roller mounted on said unit andengaging said chain, said chain drive being operable for driving saidunit in said opposite direction.

2. An apparatus according to claim 1, further comprising a limit stopdevice for adjusting said receiving and discharging positions of themovable cutting unit for an optional length of the bar advance wherebysaid bar advance which takes place during the cutting cycle said bar andsaid unit, one of said supporting rollers being positioned between saidcutting torch and said discharging rollers and the other supportingroller being positioned between said cutting torch and said transportrollers and said chain being fixed at respective ends of said track.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. l3,76'] ,178 Dated October 23, 1973 lnventofls) Alfred Pfeuffer, et al.

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

On the cover sheet item [71:] "Messer Grieshum GmbH should read MesserGriesheim GmbH Signed end sealed this 2nd day of April 1971i.

(SEAL) Attest:

EDWARD l I.FLETGHEI-l,JR. C MARSHALL DAMN Attesting Officer Commissionerof Patents JRM P0-1050 (10-69) U5COMM-DC scam-Pas 9 U.S. GOVERNMENTPRINTING OFFICE: I959 0-366-334.

1. A flame cutting apparatus, for a continuous bar selectively movablein one direction, comprising in combination, stationary transportrollers, stationary discharging rollers, a movable cutting unitincluding wheels supporting the unit for movement in said one directionand opposite thereto between a bar receiving position adjacent saidtransport rollers spaced apart from said discharging rollers, and,respectively, after moving in said one direction, a discharging positionadjacent said discharging rollers, said cutting unit further includingtwo supporting rollers for the bar, said supporting rollers beingmounted concentrically with said wheels; releasable clamping means forthe bar, control means operable for energizing said clamping means toclamp the bar thereby to insure the temporary synchronous movement ofthe bar with said movable unit in said one direction, said control meansincluding means operable for releasing said clamping means in saiddischarging position, at least one flame cutting torch positioned inadvance of said clamping means in said one direction, one of saidsupporting rollers arranged in advance of said torch in said onedirection at such a distance from said torch as to support a trailingend portion of a predetermined bar section to be cut-off when said unitis near said discharge position with the other end of the cut-off barsection supported by at least one of said discharging rollers, the majorportion of said section in said discharge position being supported bysaid discharging rollers; a chain drive including a chain extendingbetween said receiving and discharging positions, and a drive rollermounted on said unit and engaging said chain, said chain drive beingoperable for driving said unit in said opposite direction.
 2. Anapparatus according to claim 1, further comprising a limit stop devicefor adjusting said receiving and discharging positions of the movablecutting unit for an optional length of the bar advance whereby said baradvance which takes place during the cutting cycle of the unit isshorter than the predetermined length of the bar section to be cut off.3. A flame cutting apparatus according to claim 1, for cutting a barmoving in a horizontal direction from a transport roller set, said unitbeing horizontally movable along tracks by means of said moving bar,said torch moving transversally to the path of movement of said bar andsaid unit, one of said supporting rollers being positioned between saidcutting torch and said discharging rollers and the other supportingroller being positioned between said cutting torch and said transportrollers and said chain being fixed at respective ends of said track.